The Missa brevis in C Major, for 4 vocal parts and organ, was long considered one of young Mozart's excercises in The Italian style of church music. Karl Pfannhauser, after his studies of Leopold Mozart's masses, was the first to discover that the C-major fragment had been incorporated into the latter's Missa solemnis in C Major.

As Mozart was only 8 years old at the time his father wrote this mass, he cannot be deemed the composer of the fragmentary C-major mass that is listed as KV 115. Th...